Catalysts that are more functional group tolerant for polymerizing functional alkenes and show living behavior, generally produce amorphous atactic polymers.
We conceived that anilines with ortho-substituents containing stereogenic centers would be universal building blocks for a wide array of stereoselective catalysts. Our initial effort was directed to synthesis of bulky chiral substituents for incorporation into an α-diimine Ni (II) catalyst for the isospecific polymerization of trans-2-butene; this work is described in Cherian, A. E., et al., Chem. Commun. 20, 3565-2567 (2003). This work relied on the zeolite-catalyzed reaction of phenylacetylene and p-toluidine as described in Arienti, A., et al., Tetrahedron 53, 3795-3804 (1997), followed by subsequent hydrogenation of the resulting 2,6-bis(1-phenyl vinyl) anilines catalyzed by Pd/C. However, the scope of anilines that could be synthesized by this method was limited and the synthesis required two steps.